1. Field of the Invention
This invention relates to silicone oligomers useful as reactive diluents for curable polymer systems, for example, silylated polyurethanes, silylated polyethers, or mixtures thereof. These systems may be used for either high modulus sealants in automotive applications or low viscosity formulations for coatings, adhesives and sealants.
2. Description of Related Art
It is known in the art to treat fillers or reinforcing agents to improve the physical or mechanical properties of plastics, resins, or rubbers reinforced with the filler. Much of the research in this area has centered on the pretreatment of glass fiber reinforcement materials for resins and rubbers. For example, U.S. Pat. No. 3,702,783 describes the application as a size to glass fibers of a blend of 3-glycidoxypropyltri ethoxysilane and methyltrimethoxysilane. U.S. Pat. No. 3,816,235 discloses a size composition for the treatment of glass fibers wherein the size composition contains a blend of aminoalkyltriethoxysilane and methyltriethoxysilane. U.S. Pat. No. 3,944,707 discloses the use as a size for glass fiber reinforcement for plastics, blends of vinyl silane or vinyl siloxanes and a beta-haloalkoxysilane. Similarly, U.S. Pat. No. 3,993,837 discloses glass fiber size compositions containing blends of epoxyalkylsilane or siloxane and a beta-haloalkoxysilane.
U.S. Pat. No. 3,148,169, discloses the pretreatment of clay filler with a silicone fluid to coat the clay particles to impart a hydrophobic character to the clay and to mask the acidic nature of the clay so that peroxides later used as cross-linking agents are not deactivated.
U.S. Pat. No. 4,049,865 discloses glass fiber size compositions containing a blend of an aminoalkylsilane and a vinyl silane.
U.S. Pat. No. 4,130,677 discloses the sizing of glass bottle surfaces with an aminoalkylsilane.
U.S. Pat. No. 4,179,537, discloses blends of an organofunctional silane, e.g., vinyltrialkoxysilanes, methacryloxyalkyltrialkoxysilanes, vinyltrihalosilanes and the like with a non-organofunctional silane, e.g., alkyltrialkoxysilanes, and the incorporation of such blends into organic resins, e.g., EPDM rubber for improving the adhesion between inorganic substrates, such as clay fillers and the resin. This patent suggests that the presence of siloxane oligomers in the resin-filler system could have a detrimental effect on coupling efficiency (col. 4, lines 54-63). The use of silanes having silicon-bonded 2-methoxyethoxy groups as coupling agents, e.g., vinyl-tris-(2-methoxyethoxy)silane (col. 2, lines 44-47) is also described in U.S. Pat. No. 4,179,537. Vinyl-tris-(2-methoxyethoxy)silane, has been used industrially for many years as a coupling additive in mineral-filled EPM and EPDM wire and cable insulations. EPM is an ASTM designation for copolymers of ethylene and propylene; EPDM is a terpolymer of ethylene, propylene, and a diene monomer, such as ethylidene norbornene or 1,4 hexadiene. Vinyl-tris-(2-methoxyethoxy)silane has been extensively used heretofore because it provides a unique balance of elastomer reinforcement and the degree of wet electrical stability required. However, it releases 2-methoxyethanol as a hydrolysis by-product when it is used and, unfortunately, 2-methoxyethanol is now being studied as a suspected teratogen. Consequently, coupling agent products based on vinyl-tris-(2-methoxyethoxy)silane are now facing continuing replacement pressure in the marketplace.
U.S. Pat. No. 4,550,056, describes electrical cables comprising a conductor and a coating of insulation on the conductor, the coating comprising a cured composition of
(1) an organic elastomer;
(2) an inorganic filler;
(3) a coupling composition comprising (a) an ethylenically unsaturated silane, having bonded to silicon, at least one hydroxy group and/or alkoxy group; (b) a methyl ethoxy siloxane oligomer fluid; and (c) a methyl vinyl siloxane oligomer fluid.
Commercial products used as coupling agents in elastomer/filler compositions include cohydrolysis products of dimethyl and vinylmethylchlorosilanes, which are used as a filler hydrophobe treatment on calcined clays. Such products, however, have a relatively high cost owing to the high cost of vinylmethyldichlorosilane.
U.S. Pat. No. 4,950,779 describes mixtures comprising cyclic, linear, and branched alkoxy functional silicone oligomers produced by condensation of organotrialkoxysilanes, such as methyltrimethoxysilane and vinyltrimethoxysilane, using formic acid, optionally with a strong acid catalyst.
U.S. Pat. No. 5,210,168 describes alkoxy functional silicone oligomer mixtures produced from organotrialkoxysilanes using a carboxylic acid, such as formic acid, and a strong acid catalyst.
U.S. Pat. No. 5,282,998 describes mixtures of linear and cyclic alkoxy functional silicone oligomers produced from vinyltrialkoxysilanes using hydrogen chloride catalyst and water.
U.S. Pat. No. 6,140,445 describes novel alkoxy functional silicone oligomers having alkoxysilylalkyl substituents on a backbone silicon atom. Such oligomers may be produced from vinylalkoxysiloxane oligomers by hydrosilation with an alkoxyhydridosilane, by hydrosilating a vinylalkoxysilane with a hydridoalkoxy silicone oligomer, or by condensation of a bis-alkoxysilane having silicon atoms joined by other than an Sixe2x80x94O bond, optionally with other alkoxysilanes. Such oligomers are disclosed to be useful as coatings or adhesives, or additives therefor.
U.S. Pat. No. 6,207,783 discloses an oligomer of the formula:
[R3SiO1/2]m[O1/2Si(R)2O1/2]n[SiO3/2R]o[SiO4/2]pxe2x80x83xe2x80x83(I) 
wherein each R is selected individually from the group consisting of R1, xe2x80x94OR2, and xe2x80x94OR3; each R1 is independently a substituted or unsubstituted hydrocarbon group; each R2 is independently a C1-C6 alkyl group as defined for R1 or an acyl group; and each R3 is independently an alkyl or alkenyl group having at least 8 carbon atoms; with the provisos that if R3 is alkenyl, there is no unsaturation with two carbon atoms adjacent to the oxygen atom or the xe2x80x94OR3 group; at least one R group is xe2x80x94OR3; at least one quarter of all R groups are xe2x80x94OR2 or xe2x80x94OR3; m=2 to 20; n=0 to 50; o=0 to 20; and p=0 to 10. The oligomer is a useful component of insulation formulations for wire and cable used in underground locations.
U.S. Pat. No. 6,310,170 discloses compositions comprising a silylated polymer and an adhesion promoter, the silylated polymer having an inorganic or organic backbone and at least two groups thereon selected from alkoxysilyl, aryloxysilyl, alkyloximinosilyl, and silanol groups and the adhesion promoter being a silane adhesion promoter of the formula: 
R1 is a branched or cyclic alkylene group, an arylene group or an alkarylene group, any of which may be optionally interrupted by one or more ether oxygen atoms or a (poly)sulfide bridge, provided that R1 has at least 4 carbon atoms; R2 is an alkyl, aryl or alkaryl radical having 1 to 6 carbons; R3 is a C1 to C6 alkoxy group or a C3 to C5 ketoximato group; R4 is hydrogen, a hydrocarbon group, which may optionally be substituted, or a group which will thermally deblock to form an amine group containing the nitrogen atom to which it is attached; and z is 0 or 1.
U.S. Pat. No. 6,323,277 discloses oligomers of the formula:
[R3SiO1/2]m[O1/2Si(R)2O1/2]n[SiO3/2R]o[SiO4/2]pxe2x80x83xe2x80x83(I) 
wherein each R is selected individually from the group consisting of B, R1, xe2x80x94OR2, R3 and R4; B is an organosilyl functional group bridged to the Si atom of the siloxane oligomer backbone by an Sixe2x80x94C bond; each R1 is independently a saturated or aromatic hydrocarbon group of 1 to 16 carbon atoms; each R2 is independently a group as defined for R1 or an acyl group; and each R3 is independently a monovalent organic radical containing an aliphatically unsaturated hydrocarbon group and each R4 is a monovalent organic radical linked to the Si atom of the siloxane oligomer backbone by an Sixe2x80x94C bond, which does not include an aliphatically unsaturated hydrocarbon group and which has thereon one or more members selected from the group consisting of ether, polyether, ester, polyester, carbamate, polyurethane, isocyanurate, thioether, polysulfide, blocked mercaptan, amide, cyano and oximato groups; with the provisos that at least one R is a B, at least one quarter of all R groups are xe2x80x94OR2, and at least one silicon atom of the oligomer has an R3 group thereon; m=2 to 10; n=0 to 20; o=0 to 20; and p=0 to 10, which are useful as coupling agents in curable compositions of filled organic polymers used for wire and cable insulation. The oligomers also have utility as cross-linkers, as adhesion promoters, to provide a dual radical/moisture cure mechanism, and/or to provide moisture resistance in coating, in other compositions, such as curable adhesives and coatings.
U.S. Pat. No. 6,395,856 discloses oligomers of the formula:
[R3SiO1/2]m[O1/2Si(R)2O1/2]n[SiO3/2R]o[SiO4/2]pxe2x80x83xe2x80x83(I) 
wherein each R is selected individually from the group consisting of B, R1, xe2x80x94OR2, R3 and R4; B is an organosilyl functional group bridged to the Si atom of the siloxane oligomer backbone by an Sixe2x80x94C bond; each R1 is independently a saturated aliphatic hydrocarbon group of 1 to 16 carbon atoms; each R2 is independently a group as defined for R1, an aromatic hydrocarbon group or an acyl group; each R3 is independently a monovalent organic radical containing an aliphatically unsaturated hydrocarbon group and each R4 is a monovalent organic radical linked to the Si atom of the siloxane oligomer backbone by an Sixe2x80x94C bond, which does not include an aliphatically unsaturated hydrocarbon group and which has thereon one or more members of the group selected from aromatic hydrocarbon, ether, ester, carbamate, thioether, polysulfide, blocked mercaptan, amide, epoxy, cyano and oximato groups; and with the provisos that at least one quarter of all R groups are xe2x80x94OR2; either at least one silicon atom of the oligomer has an R3 group thereon or at least one R is a B, or both; if there is a group R3 which is a vinyl group, there is at least one other group which is a B group, an R3 group other than vinyl, or an R4 group; m=2 to 20; n=0 to 50; o=0 to 20; and p=0 to 10, are useful as coupling agents in curable compositions of filled organic polymers used for wire and cable insulation. The oligomers also have utility as crosslinkers, as adhesion promoters, to provide a dual radical/moisture cure mechanism, and/or to provide moisture resistance in coating, in other compositions, such as curable adhesives and coatings.
The disclosures of the foregoing are incorporated herein by reference in their entirety.
The present invention is directed to silicone oligomers similar to those disclosed in U.S. Pat. No. 6,395,856 and U.S. Pat. No. 6,323,277 characterized by having vinyl, mercapto, or other aliphatic or aromatic hydrocarbon functionality thereon, which are useful in certain cross-linkable organic polymer compositions, such as silylated prepolymers or conventional polyurethane prepolymers, for applications in coatings, adhesives, and sealants. The silicone oligomers useful in the practice of the present invention may be of the formula:
[R3SiO1/2]m[O1/2Si(R)2O1/2]n[SiO3/2R]o[SiO4/2]pxe2x80x83xe2x80x83(I) 
wherein:
each R is selected individually from the group consisting of B, R1, xe2x80x94OR2, R3, and R4;
B is an organosilyl functional group bridged to the Si atom of the siloxane oligomer backbone by a Sixe2x80x94C bond;
each R1 is independently a saturated or aromatic hydrocarbon group of 1 to 16 carbon atoms;
each R2 is independently a group as defined for R1 or an acyl group;
each R3 is independently a monovalent organic group containing an aliphatic unsaturated hydrocarbon group;
each R4 is a monovalent organic group linked to the Si atom of the siloxane oligomer backbone by a Sixe2x80x94C bond that does not include an aliphatic unsaturated hydrocarbon group and that has thereon one or more members selected from the group consisting of ether polysulfide, ester, polyester, carbamate, polyurethane, isocyanurate, thioether, blocked mercaptan, amide, cyano, and oximato groups;
with the provisos that at least one R is a B, at least one quarter of all R groups are xe2x80x94OR2, and at least one silicon atom of the oligomer has an R3 group thereon;
m is 2 to 10;
n is 0 to 20;
o is 0 to 20; and
p is 0 to 10.
In one aspect, the invention is directed to a curable composition comprising an oligomer of formula (I). Such compositions can be formed by mixing concurrently or in any order of succession:
1. an organic polymer curable by moisture;
2. a silicone oligomer as described above;
3. with or without one or more inorganic fillers, plasticisers, or other additives.
Preferred compositions also include a catalyst package capable of catalyzing silane condensation leading to the crosslinking of the organic polymer. Sealant and adhesive compositions that comprise the oligomers of formula (I) may also be prepared.
The silicone oligomers may be produced with little or no volatile material. They could be used as replacements for free isocyanates or organic solvents and used in coatings, adhesives, or sealants, thereby reducing health hazards and improving the products"" mechanical properties and adhesion to difficult substrates.
More particularly, the present invention is directed to a composition comprising:
A) a moisture curable polymer selected from the group consisting of silylated polyurethanes, silylated polyethers, and mixtures thereof, and
B) a silicone oligomer of the formula:
[R3SiO1/2]m[O1/2Si(R)2O1/2]n[SiO3/2R]o[SiO4/2]pxe2x80x83xe2x80x83(I) 
wherein:
each R is independently selected from the group consisting of B, R1, xe2x80x94OR2, R3, and R4;
B is an organosilyl functional group bridged to the Si atom of the siloxane oligomer backbone by a Sixe2x80x94C bond;
each R1 is independently a saturated or aromatic hydrocarbon group of 1 to 16 carbon atoms;
each R2 is independently a group as defined for R1 or an acyl group;
each R3 is independently a monovalent organic group containing an aliphatic unsaturated hydrocarbon group;
each R4 is a monovalent organic group linked to the Si atom of the siloxane oligomer backbone by a Sixe2x80x94C bond that does not include an aliphatic unsaturated hydrocarbon group and that has thereon one or more members selected from the group consisting of ether polysulfide, ester, polyester, carbamate, polyurethane, isocyanurate, thioether, blocked mercaptan, amide, cyano, and oximato groups;
with the provisos that at least one R is a B, at least one quarter of all R groups are xe2x80x94OR2, and at least one silicon atom of the oligomer has an R3 group thereon;
m is 2 to 10;
n is 0 to 20;
o is 0 to 20; and
p is 0 to 10.
In another aspect, the present invention is directed to an article of manufacture comprising a cured composition prepared from a composition comprising:
A) a moisture curable polymer selected from the group consisting of silylated polyurethanes, silylated polyethers, and mixtures thereof; and
B) a silicone oligomer of the formula:
[R3SiO1/2]m[O1/2Si(R)2O1/2]n[SiO3/2R]o[SiO4/2]pxe2x80x83xe2x80x83(I) 
wherein:
each R is independently selected from the group consisting of B, R1, xe2x80x94OR2, R3, and R4;
B is an organosilyl functional group bridged to the Si atom of the siloxane oligomer backbone by a Sixe2x80x94C bond;
each R1 is independently a saturated or aromatic hydrocarbon group of 1 to 16 carbon atoms;
each R2 is independently a group as defined for R1 or an acyl group;
each R3 is independently a monovalent organic group containing an aliphatic unsaturated hydrocarbon group;
each R4 is a monovalent organic group linked to the Si atom of the siloxane oligomer backbone by a Sixe2x80x94C bond that does not include an aliphatic unsaturated hydrocarbon group and that has thereon one or more members selected from the group consisting of ether polysulfide, ester, polyester, carbamate, polyurethane, isocyanurate, thioether, blocked mercaptan, amide, cyano, and oximato groups;
with the provisos that at least one R is a B, at least one quarter of all R groups are xe2x80x94OR2, and at least one silicon atom of the oligomer has an R3 group thereon;
m is 2 to 10;
n is 0 to 20;
o is 0 to 20; and
p is 0 to 10.
In still another aspect, the present invention is directed to a method for the preparation of silylated polyurethanes comprising:
A) combining a silylated polyurethane prepolymer with a silicone oligomer of the formula:
[R3SiO1/2]m[O1/2Si(R)2O1/2]n[SiO3/2R]o[SiO4/2]pxe2x80x83xe2x80x83(I) 
wherein:
each R is independently selected from the group consisting of B, R1, xe2x80x94OR2, R3, and R4;
B is an organosilyl functional group bridged to the Si atom of the siloxane oligomer backbone by a Sixe2x80x94C bond;
each R1 is independently a saturated or aromatic hydrocarbon group of 1 to 16 carbon atoms;
each R2 is independently a group as defined for R1 or an acyl group;
each R3 is independently a monovalent organic group containing an aliphatic unsaturated hydrocarbon group;
each R4 is a monovalent organic group linked to the Si atom of the siloxane oligomer backbone by a Sixe2x80x94C bond that does not include an aliphatic unsaturated hydrocarbon group and that has thereon one or more members selected from the group consisting of ether polysulfide, ester, polyester, carbamate, polyurethane, isocyanurate, thioether, blocked mercaptan, amide, cyano, and oximato groups;
with the provisos that at least one R is a B, at least one quarter of all R groups are xe2x80x94OR2, and at least one silicon atom of the oligomer has an R3 group thereon;
m is 2 to 10;
n is 0 to 20;
o is 0 to 20; and
p is 0 to 10; and
B) curing by exposure to moisture.